10 replies to this topic

[elthorr]

Hello,

 

 

please help, how do I get the cocoa powder fineness reached 99.5% (200 mesh).

 

and why fineness in cocoa powder must reached 99.5%.

 

Thanks & Regards

elthorr

[Tony-C]

Hi Elthorr,

 

For chocolate milk applications fineness helps release color and flavor, reduce sedimentation, reduces the risk of spore survival and reduces the risk of damage to the homogenizer.

 

Regards,

 

Tony

[RG3]

To add on to Tony-C's comment, not only to reduce the risk of damaging the homo but it could damage your press.

[elthorr]

thanks

[elthorr]

Thanks for the comments

 

so, what processes need to be considered to meet this parameter? because in my place there are 3 steps of grinding: pre, intermediete and fine grinding which for intermediete and fine use ball mill 6 mm.

whether raw materials also affect?

 

Thanks & Regards,

elthorr

[xylough]

Hi elthorr,

 

What I am reading in the Science of Chocolate by S. T. Beckett and other sources indicates that too much cocoa shell adulterating the nibs will interfere with fine grinding.

The reduction from nib size of several hundred microns down to cocoa powder (for chocolate ) size of about 30 microns is about  a 100 times reduction, but at each milling the best efficiency is at less than10 times reduction. As you progress through pre-grind, intermediate and fine, each milling should aim for no more than a 10 times reduction.

The literature also indicates that:

 

• the hardened steel beads/balls do wear and must be replaced at intervals (no frequency guideline given)
• bead/ball compression is to be avoided
• should allow high flow rates
• should have high cooling efficiency
• initial "pre-grind" is customarily with an impact mill
• finer cocoa powder is achieved through a two milling series of bead/ball mills with decreasing bead/ball size (bead/ball mm size for intermediate was not indicated, final milling mm bead/ball size indicated 5 or 6 mm)
• the bead mills used for cocoa mass are vertical bead mills, using 5 to 6 mm or 1/4" and 3/16" diameter steel balls, beads or shots.
• nibs must not be adulterated with cocoa shell (not to exceed 2.7%)
• with decrease in ball/bead size the agitator speed is increased (no guidelines given)
• powders (for cocoa) should be about 99.7 % < 75 microns (sieve analysis)

[elthorr]

dear xylough,

 

thanks for your explanation, I will discuss with my team about this.

Maybe can you share some references?

 

Thank you

[xylough]

Elthorr,

 

I attached the article because it has a bibliography of 17 references. The article does not speak to your question directly, but references many of the prime works on chocolate and cocoa in recent years.

 

The challenge I encountered is that many of these works have a cost to go beyond a random peek at them. The machinery, methods and goals for chocolate differ somewhat for cocoa powder in many cases,but not all.

 

With cocoa mass intended for chocolate, the goal is to granualize smaller than 30 microns (the size of a single cocoa nib cell) to allow the maximum quantity of the cocoa butter to come out and surround the cocoa particle for a smooth mouth feel.

 

With cocoa mass intended for cocoa powder, the goal is a somewhat larger particle so as to avoid problems with electrostatic charges that interfere with powdering and packaging the cocoa and additionally to retain some of the cocoa butter in the cell. As I read the literature I had to remain cognizant of which goal the information was pertinate to.

 

I suspect the exact metrics and procedure that would be most helpful to you are proprietary to manufacturers of cocoa, chocolate and of the machinery and closely held. Have you tried contacting the manufacturer of your specific ball grinder make and model for aid?

 

Kind regards

Attached Files

•  Chocolate mass processing technologies.pdf   4.16MB   49 downloads

[elthorr]

Dear xylough,

 

Thank you, this is very helpful.

I haven't tried contacting the manufacturer, perhaps soon :)

 

Terima kasih

 

Regards

[tdunkley]

Hi Tony,

Wondering if you can share any specific references that demonstrate for chocolate milk application the increasing fineness reduces the risk of spore survival? Wondering why this is the case...is it simply because temperature is more stable during the pasteurization step? I've also seen that chocolate milk requires a 3oC higher pasteurization temp. Trying to understand exactly why this is the case. Any resources you can direct me to would be appreciated. 

Regards,

Theresa

[Tony-C]

Hi Theresa,

It was a while ago so I'll have to see if I can find the original source, I'm pretty sure it was Tetra-Pak guidance. The theory is that the finer powder offers less protection to any spores present and thus the process is more effective in deactivating them.

Kind regards,

Tony